Purchasing the Perfect Size Air Conditioning Unit

How to Calculate your Air Conditioning Unit Size

Air conditioners are great for cooling us off during the hot summer months, but if you don’t choose the right unit you may never get that cool comfortable summer that you deserve.
Tips for purchasing a room air conditioning unit

A great way to cool a room on those hot summer days is by using a window air conditioner.  Did you know that  purchasing a bigger room air conditioning unit will not necessarily cool your room more efficiently during the heat of the summer?

The fact is that a room air conditioner that’s too large for the area  will perform less efficiently then a properly sized unit. And a unit that is too small for the room will not have enough BTU’s (British Thermal Units)  to cool the room at a comfortable cooling level. The cooking capacity of the unit is measured in BTU’s (British Thermal Units), the more BTU’s it has , the more space it will cool down.  If the unit doesn’t have enough BTU’s, the room never will become cool and comfortable. So before you buy that air conditioner you first need to figure out what size you will need for the room your looking to cool off.

And here is how you will calculate what size unit you will need for that room.  You need to measure the length, width  and height of the room. Then multiply the length times the width times the height will give you the calculated volume number of the room.

Now, you’ll need to figure out which direction the most exposed wall of the room faces. That is, which wall of the room is most exposed to the outside elements. Look around the room to find the answer- is it east? north? south? or west? Look at east as having a value of 17; west as having a value of 20; north’s value is 16, and south is 18. Use the volume of the room and multiply that number by the corresponding number for whatever direction you choose.

Finally, in order to find out what size of a window air conditioner you’ll need to purchase for your room, divide the result you last arrived at by the number which corresponds most accurately to the level of your home’s insulation. If your home has poor insulation, use a 4. If the insulation is good, use a 5. And, if the insulation  in your home is excellent, then use the number 6.

The result of these calculations will give you the approximate number of BTU’s your new air conditioner will need to have.

Here is an example of a bedroom with the correct size room air conditioner.

I purchased a window air conditioner for this room, and the formula described above gave me the perfect size. My living room is 17 feet long, 15 feet wide, and 9 feet high. So I multiplied 17 by 15 by 9 which equals 2,295. The wall that is most exposed to the outside elements is the north side. The value for north is 16.  I multiplied the 2295 by 16. The resulting calculation is 36,720. Next, I determined that the insulation level of my home is good. A “good”  is a number 5. Finally, I divided 36,720 by 5. The resulting number is 7,344. After I rounded it off, this told me that I needed to purchase a 7,000 BTU air conditioner. They come in sizes from 5,000 BTU’s all the way up to 24,000.

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  1. home insulations should be made out of fire resistant material too~;`

  2. our home insulation are always made out of polystyrene foams, my friend also suggested the use of polyurrethane foams`-“

  3. home insulation would be much needed this coming Christmas so i am scouting the local hardware for some supplies :

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